length=cv2.arcLength(curve,colosed)
area=cv2.contourArea(contour)
import cv2
image=cv2.imread('sobel.png',cv2.COLOR_BGR2GRAY)
image=cv2.GaussianBlur(image,(5,5),0)
edges=cv2.Canny(image,50,150)
contours,hierarchy=cv2.findContours(edges,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPPLE)
n=len(contours)
for i in range(n):
    length=cv2.arcLenth(contours[i],True)
    area=cv2.contourArea(contours[i])
    print("轮廓+str(i)+的周长:"+str(length))
    print("轮廓+str(i+的面积:"+str(area))